Introduction to SQL: 5 Key Concepts Every Data Professional Must Know
Master the basics of SQL with PostgreSQL, DVD rental database, and this beginner-friendly guide.
Published in
6 min readJan 27, 2021
SQL has been around for decades, and is a go-to language for data analysis and lookups. With the rise of data-related programming languages such as R and Python, it’s easy to use SQL only for a simple SELECT * statement and perform the filterings and aggregations later. While tempting, that’s not the best solution.
Today you’ll learn the basics of SQL through a ton of hands-on examples. You’ll need to have a PostgreSQL database installed to follow along.
The article is structured as follows:
- Dataset introduction
- Select data
- Filter data
- Sort data
- Match data
- Join and group data
- Conclusion
Dataset introduction
As briefly mentioned earlier, you’ll need to have the PostgreSQL database installed. You’ll also need the Dvd Rental dataset that you can load to your database via the restore functionality.
